Consumers looking to purchase a pool enjoy a wide variety of choices in construction materials. These materials offer various advantages and disadvantages with regard to initial and lifetime costs, availability in terms of shape and size, maintenance requirements and installation time. However, regardless of whether the pool is constructed from polyvinyl chloride, reinforced polyester, granite, or concrete, they all have slippery surfaces when wet. This is a common concern in the normal course of pool usage but can become especially problematic when pool pH values vary, or the chemical balance of the pool otherwise becomes unbalanced, allowing algae to grow. The presence of algae increases the slipperiness of the pool surfaces and creates a possibly dangerous situation for swimmers as they move across step surfaces within the pool or the pool bottom. Similar concerns exist with regard to wet surfaces in and around spas, showers, bathtubs and boats.
While conventional slip-resistant materials, such as treads, are generally available to reduce the slipperiness of surfaces, they are not typically suitable for pools in that they often contain large abrasive particles that could injure a swimmer's bare feet, and in any event are designed for installation under dry conditions. Further, while various products can be used to increase the coefficient of friction for a pool surface, none of these can be applied after the pool has been filled with water. Removing water from the pool is possible, however, it is costly, time consuming, and in the case of a pool having a polyvinyl chloride liner, may even compromise the structural integrity of the liner in the pool if not done properly by a professional. Therefore, work has been ongoing to produce articles having improved anti-slip properties that can be used on surfaces partially or totally covered by water, such as pools.
U.S. Pat. No. 6,509,084 discloses an approach for increasing the surface coefficient of friction of high density polyethylene (HDPE) products by mechanically forming a rough surface texture on the thermoplastic material by embossing its surface as it is molded.
U.S. Pat. No. 4,693,507 discloses a method for increasing the coefficient of friction on an HDPE liner surface by applying a continuous film or layer of elastomeric material over the HDPE sheet. The elastomeric film layer can be applied to the HDPE sheet by lamination, by adhesive or application of heat.
U.S. Pat. Nos. 5,648,031 and 6,509,084 disclose preparation of a polyolefin, such as HDPE, ABS, PVC, PET. nylon, and PMMA, haying an anti-slip surface. The surface is composed of individual non-interconnected asperities of an anti-slip polymeric material that do not form a continuous film over the surface.
U.S. Pat. No. 5,645,912 discloses a method for making anti-skid/anti-slip staircase treads by affixing the tread to the stair nose with the use of a sealant and a detachable anti-skid/anti-slip conformable tape made out of aluminum. The flexible tape may have particulate matter securely attached to the upper surface for improved anti-skid traction.
U.S. Pat. No. 7,125,599 discloses methods for preparation of anti-slip surfaces around and near swimming pools that include: a) textured roughened rubberized surfaces that may include grooves: or b) a grit of sandpaper-like finish, where the finish is typically an adhesively attached sheet with the grit finish.
U.S. Pat. No. 3,676,198 discloses the application of granular bentonite material to a substrate by mixing it with a carbohydrate-based adhesive substrate.
U.S. Pat. No. 3,575,780 discloses the use of ground rubber or cork, bonded by PVC, acrylic resins or polyisobutylene using thermoplastic molding materials, such as a combination of bitumen with ethylene-butylacrylate copolymer, for coating the surface of a playing field.
U.S. Pat. No. 3,547,674 discloses the use of crumb rubber, which is compacted and oriented during preparation of a playing field surface.
U.S. Pat. No. 3,745,034 discloses the deposition of metallic powder on a metal strip by electrostatic technique using a gaseous aerosol.
U.S. Pat. No. 4,243,696 discloses a method for producing a particle-containing plastic coating on articles. The method comprises applying a mixture of powdered epoxy resin and a particulate material (alumina grit, silicon carbide grit, silica sand grit, glass particles, quartz grit or fiberglass) and curing the dry blend onto the surface by heating.
U.S. Pat. No. 4,336,293 discloses preparation of a plasticized PVC anti-slip mat covered by polyamide primer, which is spray coated with a polyurethane adhesive material containing alumina grit and then cured at 180° C.
U.S. Pat. No. 4,745,139 discloses surface coating formulations for application to surfaces that are in frequent contact with water for providing surface roughness and for increasing anti slip characteristics. The formulation comprises a styrene/ethylene/butylene/styrene block co-polymer, finely divided silicon dioxide filler, a solvent solution of methylmethacrylate copolymer solids, rubber tackifier and glass microspheres.
U.S. Pat. No. 5,494,729 discloses a non-slip coated substrate comprising a solid polysulfide film and a layer of rubber particles partially bonded to the film.
Nevertheless, a continuing need exists for a process to install water-resistant anti-slip articles on a surface that is at least partially covered with water.